Proton NMR Analysis of Octane Number for Motor Gasoline: Part IV

1992 ◽  
Vol 46 (8) ◽  
pp. 1294-1300 ◽  
Author(s):  
M. Ichikawa ◽  
N. Nonaka ◽  
H. Amano ◽  
I. Takada ◽  
S. Ishimori ◽  
...  

Software (a program) for predicting the octane number of motor gasoline by proton magnetic resonance (PMR) spectrometry has been formulated. At the same time, a method has been studied to predict the composition of gasoline (in terms of the contents of paraffin, olefin, and aromatic compounds). The formulated program was evaluated by using it to predict the octane numbers of 31 samples of marketed summer gasoline (including 16 regular and 15 premium products), whose octane numbers and compositions were identified according to the ASTM standards. Also, the relationship between the PMR spectrum and gasoline composition was subjected to linear regression analysis by using the 31 samples whose octane numbers were calculated, and the appropriateness of the resultant regression equations was assessed. This report concerns the results of the study in which the octane numbers of the 31 samples were satisfactorily predicted by the formulated program and useful linear regression equations were obtained for the prediction of the composition of gasoline.

2020 ◽  
Vol 27 (4) ◽  
pp. 303-312 ◽  
Author(s):  
Ruifang Li ◽  
Hong Li ◽  
Sarula Yang ◽  
Xue Feng

Background: It is currently believed that protein folding rates are influenced by protein structure, environment and temperature, amino acid sequence and so on. We have been working for long to determine whether and in what ways mRNA affects the protein folding rate. A large number of palindromes aroused our attention in our previous research. Whether these palindromes do have important influences on protein folding rates and what’s the mechanism? Very few related studies are focused on these problems. Objective: In this article, our motivation is to find out if palindromes have important influences on protein folding rates and what’s the mechanism. Method: In this article, the parameters of the palindromes were defined and calculated, the linear regression analysis between the values of each parameter and the experimental protein folding rates were done. Furthermore, to compare the results of different kinds of proteins, proteins were classified into the two-state proteins and the multi-state proteins. For the two kinds of proteins, the above linear regression analysis were performed respectively. Results : Protein folding rates were negatively correlated to the palindrome frequencies for all proteins. An extremely significant negative linear correlation appeared in the relationship between palindrome densities and protein folding rates. And the repeatedly used bases by different palindromes simultaneously have an important effect on the relationship between palindrome density and protein folding rate. Conclusion: The palindromes have important influences on protein folding rates, and the repeatedly used bases in different palindromes simultaneously play a key role in influencing the protein folding rates.


2018 ◽  
Vol 10 (3) ◽  
pp. 226
Author(s):  
Maksimus Bisa

ABSTRACTThis study is descriptive analitik, aims to describe the relationship of perceptions about the physiotherapy profession with the motivation to learn students of the Academy of Physiotherapy UKI. Data collection through questionnaires to students of Physiotherapy Academy UKI level 1, 2, and 3 with a sample of 53 students, then give a score of each statement of questionnaire.The result of correlation analysis shows that p = 0,584> α (0,05) ho is accepted, so there is no significant relationship between the two variables. To measure the closeness and intensity of the relationship between the two variables, test of correlation coefficient and simple linear regression. The result of correlation coefficient test (r) obtained by -0,077, lies below the value of -0.30 (very weak) thus can be said there is no relation between perception about physiotherapy profession with motivation learn student Akfis UKI. Result of linear regression analysis obtained equation: Y = 73,52 + (-0,088) X. This means that every 1 point decrease of perception value will influence motivation value equal to 0,088 times.Keywords: Perception, motivation, physiotherapy profession, and learning achievement. ABSTRAKPenelitian ini bersifat deskriptif analitik, bertujuan untuk mendeskripsikan hubungan persepsi tentang profesi fisioterapi dengan motivasi belajar siswa Akademi Fisioterapi UKI. Pengumpulan data melalui kuesioner kepada siswa Fisioterapi Academy UKI tingkat 1, 2, dan 3 dengan sampel sebanyak 53 siswa, kemudian memberikan skor masing-masing kuesioner pernyataan. Hasil analisis korelasi menunjukkan bahwa p = 0,584> α (0,05) ho diterima, sehingga tidak ada hubungan yang signifikan antara kedua variabel tersebut. Untuk mengukur kedekatan dan intensitas hubungan antara kedua variabel tersebut, uji koefisien korelasi dan regresi linier sederhana. Hasil uji koefisien korelasi (r) diperoleh sebesar -0,077, berada di bawah nilai -0,30 (sangat lemah) sehingga dapat dikatakan tidak ada hubungan antara persepsi tentang profesi fisioterapi dengan motivasi belajar siswa Akfis UKI. Hasil analisis regresi linier diperoleh persamaan: Y = 73,52 + (-0,088) X. Artinya setiap 1 titik penurunan nilai persepsi akan mempengaruhi nilai motivasi sebesar 0,088 kali.Kata kunci: Persepsi, motivasi, profesi fisioterapi, dan prestasi belajar.


2020 ◽  
Vol 3 (2) ◽  
pp. 144-152
Author(s):  
Ermayanis Ermayanis ◽  
Nurse Fatimah MZ

This study aimed to determine the effect of promotion on the sales of Islamic insurance policies at PT. Asuransi Takaful Keluarga RO Riau Agency Pekanbaru. This research was motivated by the development of Islamic insurance companies both in terms of assets and in terms of company contributions that have an impact on insurance policy sales. The formulation of the problem in this study was to determine the effect of the relationship promotion on insurance policy sales. This research used quantitative methods with simple linear regression analysis. The sample in this study was 49 respondents. Based on the results of the partial test (t-test), the tcount was 1.391 <t-table 2.016, so the promotion had no significant effect on the variable sales of the insurance policy of PT. Asuransi Takaful Keluarga RO Riau Pekanbaru. The regression results showed that the promotion variable does not affect sales.


2019 ◽  
Author(s):  
Esther Iriagbonse Eroje ◽  
Erasmus Kofi Appiah ◽  
Alezi Braimoh Ifindon Eroje ◽  
MEER ZAKIRULLA ◽  
Jimly James Kunjappu ◽  
...  

Abstract Background Leadership has become the key issues in managing the organization, the emerging business and economic environments have forced organizations to be flexible, adaptive, entrepreneurial and innovative to meet changing demand of the present-day business environment. The purpose of the present study is to examine the relationship between the various dimensions of transformational leadership (predictor variable) and their effects on employees’ job satisfaction (criterion variable) in three selected Colleges (Medicine, Dentistry and Science) in King Khalid University. Methods The methodology employed in this study was a quantitative and cross-sectional correlational survey type of design Data collection was done using a questionnaire design that was directly administered to the participants. 250 questionnaires were sent to the participating three colleges (Medicine, Dentistry and Sciences). Results The findings of the multiple linear regression analysis indicated a weak positive association between transformational leadership behaviour and employees’ job satisfaction (R-value 0.386). The multiple linear regression analysis signifies a weak positive correlation between transformational leadership behaviour and job satisfaction (R-value 0.386). A p-value in Spearman’s rho that is less than the 0.05 level of significance indicated that there is a significant level of relationship which exists between transformational leadership behaviour and job satisfaction. Conclusions This study concluded that transformational leadership behaviour and its four dimensions showed a weak positive correlation with a statistically significant level of relationship between transformational leadership behaviour and employees’ job satisfaction among three selected colleges (Medicine, Dentistry and Sciences) in King Khalid University, Abha, Saudi Arabia.


2017 ◽  
Vol 12 (4) ◽  
pp. 55
Author(s):  
Marisol Sanchez Guerrero ◽  
Alejandro Arellano Gonzalez ◽  
Nidia J. Rios Vazquez

The objective of this research is to analyze the influence of strategic management on competitiveness and organizational performance, an issue that is present in micro, small and medium-sized enterprises in the food and beverage preparation industry of the service sector. The study sample was of 200 Mexican organizations from Ciudad Obregón, Sonora. The results indicated that strategic management has a positive, direct and significant effect on competitiveness. The results that were obtained by means of linear regression analysis make it possible to assert that the interaction between both variables (strategic management and competitiveness) establishes significant differences in the levels of organizational performance. It was concluded that the enhancement of strategic management contributes to the increase in organizational performance. Therefore, a joint intervention must take place on strategic management and competitiveness.


1968 ◽  
Vol 46 (4) ◽  
pp. 787-796 ◽  
Author(s):  
Stephen J. Nicola

The relationship between stonefly nymphs of the genus Alloperla and developing pink and chum salmon embryos was studied in Harris River, Alaska, from August, 1965, to April, 1966. Polyethylene containers with alternating layers of salmon eggs and washed gravel and containers with washed gravel only were buried in sections of an upstream spawning riffle and were removed and examined in three sampling periods. Correlation and linear regression analysis of numbers of missing embryos, dead embryos, and stonefly nymphs in the containers supported the hypothesis that the nymphs were scavengers but failed to support the hypothesis that they were predators.Some of the beneficial effects to living embryos of scavenging by nymphs is discussed, as well as the likelihood of occurrence of predation by stonefly nymphs in general.


2015 ◽  
Vol 1120-1121 ◽  
pp. 1115-1118
Author(s):  
Peng Cheng ◽  
Xian Qiu Huang

Aimed at the corrosion problem of DH36 steel in the seawater full immersion zone, corrosion environment of full immersion zone has been simulated with artificial seawater in laboratory. The corrosion behaviors of DH36 steel in the full immersion zone were investigated by using full immersion tests. The morphology of corrosion products was observed by SEM. Using linear regression analysis to establish the relationship between temperature and the corrosion of DH36 steel. The results showed that the corrosion of DH36 steel immersed in full immersion zone corroded seriously, and the corrosion rate of DH36 steel increased with temperature increasing.


2009 ◽  
Vol 79 (6) ◽  
pp. 1162-1168 ◽  
Author(s):  
Marian Almyra Sevilla-Naranjilla ◽  
Ingrid Rudzki-Janson

Abstract Objective: To construct a harmony box based on correlated cephalometric variables, which may serve as a valuable diagnostic tool in orthodontic treatment planning, by analyzing the harmonious relationships of existing individual craniofacial patterns among Filipinos. Materials and Methods: Eighty-one subjects, 37 females and 44 males, were selected from the student population of a University according to established inclusion criteria. Five cephalometric angular measurements were obtained and digitized. Pearson correlation coefficients described the high association among the five variables. The bivariate linear regression analysis was used to construct a harmony box, which contained the cephalometric floating norms of the five correlated variables. Multiple regression analysis and the standard error of the estimate were calculated to construct the harmony schema, which describes the individual craniofacial pattern. Results: Correlations between the five variables were significant at .001 and .05 levels. Linear regression equations with corresponding r2 and standard error of the estimate (SE) were illustrated as the harmony box. The multiple correlation coefficient R, the adjusted R2, and the SE when one of the five measured variables was predicted from the remaining four by means of a multiple regression analysis were displayed as the harmony schema. Conclusion: The cephalometric floating norms describing the individual craniofacial pattern among Filipinos were established based on five correlated variables in the form of a harmony box.


2021 ◽  
Author(s):  
Yanru Guo ◽  
Xianyang Zhu

Abstract Purpose: To research the relationship between serum creatinine and lumbar bone mineral density in people aged <46 years. Methods: A total of 10,968 subjects from the American Nhanes database were included in this cross-sectional study, including 5,744 males (mean age 26.2 years) and 5224 females (mean age 26.7 years). The exposure factor is the serum creatinine value, and the outcome indicator is the lumbar bone mineral density. This study mainly used multivariate linear regression analysis to test the relationship between lumbar bone mineral density and serum creatinine. Results: In the multivariate linear regression analysis, serum creatinine was positively correlated with lumbar bone mineral density (β = 0.122, 95%CI: 0.047-0.198), but in the subgroup analysis stratified by sex, this positive correlation only exists in the female population (Β = 0.186, 95%CI: 0.070-0.301).Conclusions: Our study found that in women aged <46 years with normal renal function, there is a positive correlation between serum creatinine and lumbar BMD. And in those people, the determination of serum creatinine can provide a sensitive biomarker for the early identification and treatment of Osteopenia or osteoporosis.


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